The invention concerns a method of determining geometrical data of a motor vehicle wheel mounted rotatably about an axis of rotation and an apparatus for carrying out that method.
A method and an apparatus of that kind are known from EP 1 174 698 A2. In the known method and the known apparatus the motor vehicle wheel which can be fixed rotatably on the main shaft of a wheel balancing machine is scanned in a contactless mode, for example by means of a laser beam. The reflected beam is received by a position-sensitive receiver and the spacing of the scanned measurement points is measured. The spacings between a plurality of measurement points are used to determine the profile of the motor vehicle wheel, in terms of optimising the balancing operation.
When fixing the motor vehicle wheel to a rotatable wheel mounting, for example the main shaft of a wheel balancing machine or to the rotatable wheel fixing of a motor vehicle wheel or another wheel fixing, there is the danger that the geometrical axis of the wheel does not coincide with the axis of rotation about which the wheel rotates, for example in an unbalance measuring run or while the motor vehicle is travelling. The geometrical axis of the wheel can be eccentric with respect to the axis of rotation and/or can involve an angle of inclination relative to the axis of rotation.